1
|
Cao W, Zhao J, Qu P, Liu E. Current Progress and Prospects in Rabbit Cloning. Cell Reprogram 2022; 24:63-70. [PMID: 35167365 DOI: 10.1089/cell.2021.0090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Somatic cell nuclear transfer (SCNT) shows great value in the generation of transgenic animals, protection of endangered animals, and stem cell therapy. The combination of SCNT and gene editing has produced a variety of genetically modified animals for life science and medical research. Rabbits have unique advantages as transgenic bioreactors and human disease models; however, the low SCNT efficiency severely impedes the application of this technology. The difficulty in SCNT may be attributable to the abnormal reprogramming of somatic cells in rabbits. This review focuses on the abnormal reprogramming of cloned mammalian embryos and evaluates the progress and prospects of rabbit somatic cell cloning.
Collapse
Affiliation(s)
- Wenbin Cao
- Laboratory Animal Center, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Jinpeng Zhao
- Laboratory Animal Center, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Pengxiang Qu
- Laboratory Animal Center, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Enqi Liu
- Laboratory Animal Center, Xi'an Jiaotong University Health Science Center, Xi'an, China
| |
Collapse
|
2
|
Use of Genome Editing Techniques to Produce Transgenic Farm Animals. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1354:279-297. [PMID: 34807447 PMCID: PMC9810480 DOI: 10.1007/978-3-030-85686-1_14] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Recombinant proteins are essential for the treatment and diagnosis of clinical human ailments. The availability and biological activity of recombinant proteins is heavily influenced by production platforms. Conventional production platforms such as yeast, bacteria, and mammalian cells have biological and economical challenges. Transgenic livestock species have been explored as an alternative production platform for recombinant proteins, predominantly through milk secretion; the strategy has been demonstrated to produce large quantities of biologically active proteins. The major limitation of utilizing livestock species as bioreactors has been efforts required to alter the genome of livestock. Advancements in the genome editing field have drastically improved the ability to genetically engineer livestock species. Specifically, genome editing tools such as the CRISPR/Cas9 system have lowered efforts required to generate genetically engineered livestock, thus minimizing restrictions on the type of genetic modification in livestock. In this review, we discuss characteristics of transgenic animal bioreactors and how the use of genome editing systems enhances design and availability of the animal models.
Collapse
|
3
|
Abstract
Germline editing, the process by which the genome of an individual is edited in such a way that the change is heritable, has been applied to a wide variety of animals [D. A. Sorrell, A. F. Kolb, Biotechnol. Adv. 23, 431-469 (2005); D. Baltimore et al., Science 348, 36-38 (2015)]. Because of its relevancy in agricultural and biomedical research, the pig genome has been extensively modified using a multitude of technologies [K. Lee, K. Farrell, K. Uh, Reprod. Fertil. Dev. 32, 40-49 (2019); C. Proudfoot, S. Lillico, C. Tait-Burkard, Anim. Front. 9, 6-12 (2019)]. In this perspective, we will focus on using pigs as the model system to review the current methodologies, applications, and challenges of mammalian germline genome editing. We will also discuss the broad implications of animal germline editing and its clinical potential.
Collapse
|
4
|
Gong G, Zhang W, Xie L, Xu L, Han S, Hu Y. Expression of a recombinant anti-programed cell death 1 antibody in the mammary gland of transgenic mice. Prep Biochem Biotechnol 2020; 51:183-190. [PMID: 32808868 DOI: 10.1080/10826068.2020.1805755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Nivolumab, a fully human IgG4 anti-programed cell death 1(PD-1)antibody, is recently one of the most popular and successful therapeutic monoclonal antibodies in clinical use. With the increasing demands for Nivolumab and other therapeutic monoclonal antibodies, the mammary gland bioreactor has been regarded as another choice for the production of recombinant monoclonal antibodies besides mammalian cell culture. Here, we expressed a recombinant human anti-PD-1 antibody in the mammary glands of transgenic mice. Two expression vectors were constructed bearing the heavy and light chains of anti-PD-1 antibody respectively under the control of bovine αs1-casein promoter. Transgenic mice were then generated by co-microinjection of the two expression cassettes. Three F0 founders with both heavy chain and light chain positive were obtained. Transgenes of both chains were detected to be stably transmitted to the offspring. The recombinant antibody was detected in the milk of transgenic mice with the highest expression level up to 80.52 ± 0.82 mg/L and could specifically binds to the human PD-1 antigen. Therefore, our results suggest the feasibility of anti-PD-1 antibody production in the milk of transgenic animals.
Collapse
Affiliation(s)
- Guihua Gong
- China State Institute of Pharmaceutical Industry, Shanghai, P. R. China
| | - Wei Zhang
- China State Institute of Pharmaceutical Industry, Shanghai, P. R. China
| | - Liping Xie
- China State Institute of Pharmaceutical Industry, Shanghai, P. R. China
| | - Lei Xu
- China State Institute of Pharmaceutical Industry, Shanghai, P. R. China
| | - Shu Han
- China State Institute of Pharmaceutical Industry, Shanghai, P. R. China
| | - Youjia Hu
- China State Institute of Pharmaceutical Industry, Shanghai, P. R. China
| |
Collapse
|
5
|
Hryhorowicz M, Lipiński D, Hryhorowicz S, Nowak-Terpiłowska A, Ryczek N, Zeyland J. Application of Genetically Engineered Pigs in Biomedical Research. Genes (Basel) 2020; 11:genes11060670. [PMID: 32575461 PMCID: PMC7349405 DOI: 10.3390/genes11060670] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/16/2020] [Accepted: 06/17/2020] [Indexed: 02/07/2023] Open
Abstract
Progress in genetic engineering over the past few decades has made it possible to develop methods that have led to the production of transgenic animals. The development of transgenesis has created new directions in research and possibilities for its practical application. Generating transgenic animal species is not only aimed towards accelerating traditional breeding programs and improving animal health and the quality of animal products for consumption but can also be used in biomedicine. Animal studies are conducted to develop models used in gene function and regulation research and the genetic determinants of certain human diseases. Another direction of research, described in this review, focuses on the use of transgenic animals as a source of high-quality biopharmaceuticals, such as recombinant proteins. The further aspect discussed is the use of genetically modified animals as a source of cells, tissues, and organs for transplantation into human recipients, i.e., xenotransplantation. Numerous studies have shown that the pig (Sus scrofa domestica) is the most suitable species both as a research model for human diseases and as an optimal organ donor for xenotransplantation. Short pregnancy, short generation interval, and high litter size make the production of transgenic pigs less time-consuming in comparison with other livestock species This review describes genetically modified pigs used for biomedical research and the future challenges and perspectives for the use of the swine animal models.
Collapse
Affiliation(s)
- Magdalena Hryhorowicz
- Department of Biochemistry and Biotechnology, Poznan University of Life Sciences, Dojazd 11, 60-632 Poznań, Poland; (D.L.); (A.N.-T.); (N.R.); (J.Z.)
- Correspondence:
| | - Daniel Lipiński
- Department of Biochemistry and Biotechnology, Poznan University of Life Sciences, Dojazd 11, 60-632 Poznań, Poland; (D.L.); (A.N.-T.); (N.R.); (J.Z.)
| | - Szymon Hryhorowicz
- Institute of Human Genetics, Polish Academy of Sciences, Strzeszyńska 32, 60-479 Poznań, Poland;
| | - Agnieszka Nowak-Terpiłowska
- Department of Biochemistry and Biotechnology, Poznan University of Life Sciences, Dojazd 11, 60-632 Poznań, Poland; (D.L.); (A.N.-T.); (N.R.); (J.Z.)
| | - Natalia Ryczek
- Department of Biochemistry and Biotechnology, Poznan University of Life Sciences, Dojazd 11, 60-632 Poznań, Poland; (D.L.); (A.N.-T.); (N.R.); (J.Z.)
| | - Joanna Zeyland
- Department of Biochemistry and Biotechnology, Poznan University of Life Sciences, Dojazd 11, 60-632 Poznań, Poland; (D.L.); (A.N.-T.); (N.R.); (J.Z.)
| |
Collapse
|
6
|
Successful genetic modification of porcine spermatogonial stem cells via an electrically responsive Au nanowire injector. Biomaterials 2019; 193:22-29. [DOI: 10.1016/j.biomaterials.2018.12.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 11/06/2018] [Accepted: 12/07/2018] [Indexed: 12/13/2022]
|
7
|
Chung HJ, Park HJ, Baek SY, Park JK, Lee WY, Kim KW, Jo YM, Hochi S, Kim YM, Choi TJ, Cho ES, Cho KH. Production of human tissue-type plasminogen activator (htPA) using in vitro cultured transgenic pig mammary gland cells. Anim Biotechnol 2018; 30:317-322. [PMID: 30522372 DOI: 10.1080/10495398.2018.1521824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Tissue plasminogen activator (tPA) is a protein involved in the breakdown of blood clots. We have previously produced a human tPA (htPA)-overexpressing transgenic pig using a mammary gland-specific promoter. In this study, we have established a transgenic pig mammary gland cell line that produces recombinant htPA. The mammary gland cells grew well and retained their character over long periods of culture. There was no difference in the extent of apoptosis in transgenic cells compared to wild-type mammary gland cells. In addition, the transgenic mammary gland cells expressed and secreted htPA into the conditioned media at a concentration similar to that in milk. This transgenic cell line represents a simple and ethical method for recombinant htPA production.
Collapse
Affiliation(s)
- Hak-Jae Chung
- Swine Science Division, National Institute of Animal Science , Cheoan-si , Republic of Korea
| | - Hyun-Jung Park
- Department of Stem Cell and Regenerative Biology, Konkuk University , Seoul , Republic of Korea
| | - Sun-Young Baek
- Swine Science Division, National Institute of Animal Science , Cheoan-si , Republic of Korea
| | - Jin-Ki Park
- Department of Swine & Poultry Science, Korea National College of Agriculture and Fisheries , Jeonju , Republic of Korea
| | - Won-Young Lee
- Department of Beef & Dairy Science, Korea National College of Agriculture and Fisheries , Jeonju , Republic of Korea
| | - Kyung-Woon Kim
- Animal Biotechnology Division, National Institute of Animal Science , Wanju-gun , Republic of Korea
| | - Yu-Mi Jo
- Medi Kinetics Central Research Institute , Gyeonggi-do , Republic of Korea
| | - Shinichi Hochi
- Interdisciplinary Graduate School of Science and Technology, Shinshu University , Ueda , Nagano , Japan
| | - Yong-Min Kim
- Swine Science Division, National Institute of Animal Science , Cheoan-si , Republic of Korea
| | - Tae-Jeong Choi
- Swine Science Division, National Institute of Animal Science , Cheoan-si , Republic of Korea
| | - Eun-Suek Cho
- Swine Science Division, National Institute of Animal Science , Cheoan-si , Republic of Korea
| | - Kyu-Ho Cho
- Swine Science Division, National Institute of Animal Science , Cheoan-si , Republic of Korea
| |
Collapse
|
8
|
Yao J, Huang J, Zhao J. Genome editing revolutionize the creation of genetically modified pigs for modeling human diseases. Hum Genet 2016; 135:1093-105. [DOI: 10.1007/s00439-016-1710-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 07/06/2016] [Indexed: 01/03/2023]
|
9
|
Mukherjee A, Garrels W, Talluri TR, Tiedemann D, Bősze Z, Ivics Z, Kues WA. Expression of Active Fluorophore Proteins in the Milk of Transgenic Pigs Bypassing the Secretory Pathway. Sci Rep 2016; 6:24464. [PMID: 27086548 PMCID: PMC4834472 DOI: 10.1038/srep24464] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 03/30/2016] [Indexed: 12/12/2022] Open
Abstract
We describe the expression of recombinant fluorescent proteins in the milk of two lines of transgenic pigs generated by Sleeping Beauty transposon-mediated genetic engineering. The Sleeping Beauty transposon consisted of an ubiquitously active CAGGS promoter driving a fluorophore cDNA, encoding either Venus or mCherry. Importantly, the fluorophore cDNAs did not encode for a signal peptide for the secretory pathway, and in previous studies of the transgenic animals a cytoplasmic localization of the fluorophore proteins was found. Unexpectedly, milk samples from lactating sows contained high levels of bioactive Venus or mCherry fluorophores. A detailed analysis suggested that exfoliated cells of the mammary epithelium carried the recombinant proteins passively into the milk. This is the first description of reporter fluorophore expression in the milk of livestock, and the findings may contribute to the development of an alternative concept for the production of bioactive recombinant proteins in the udder.
Collapse
Affiliation(s)
- Ayan Mukherjee
- Friedrich-Loeffler-Institut, Institut für Nutztiergenetik, Mariensee, Germany
| | - Wiebke Garrels
- Medical School Hannover, Institute of Laboratory Animal Sciences, Hannover, Germany
| | | | - Daniela Tiedemann
- Friedrich-Loeffler-Institut, Institut für Nutztiergenetik, Mariensee, Germany
| | - Zsuzsanna Bősze
- NARIC- Agricultural Biotechnology Institute, Gödöllö, Hungary
| | | | - Wilfried A. Kues
- Friedrich-Loeffler-Institut, Institut für Nutztiergenetik, Mariensee, Germany
| |
Collapse
|
10
|
Oviduct-specific expression of human neutrophil defensin 4 in lentivirally generated transgenic chickens. PLoS One 2015; 10:e0127922. [PMID: 26020529 PMCID: PMC4447378 DOI: 10.1371/journal.pone.0127922] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 04/20/2015] [Indexed: 11/19/2022] Open
Abstract
The expression of oviduct-specific recombinant proteins in transgenic chickens is a promising technology for the production of therapeutic biologics in eggs. In this study, we constructed a lentiviral vector encoding an expression cassette for human neutrophil defensin 4 (HNP4), a compound that displays high activity against Escherichia coli, and produced transgenic chickens that expressed the recombinant HNP4 protein in egg whites. After the antimicrobial activity of the recombinant HNP4 protein was tested at the cellular level, a 2.8-kb ovalbumin promoter was used to drive HNP4 expression specifically in oviduct tissues. From 669 injected eggs, 218 chickens were successfully hatched. Ten G0 roosters, with semens identified as positive for the transgene, were mated with wild-type hens to generate G1 chickens. From 1,274 total offspring, fifteen G1 transgenic chickens were positive for the transgene, which was confirmed by PCR and Southern blotting. The results of the Southern blotting and genome walking indicated that a single copy of the HNP4 gene was integrated into chromosomes 1, 2, 3, 4, 6 and 24 of the chickens. As expected, HNP4 expression was restricted to the oviduct tissues, and the levels of both transcriptional and translational HNP4 expression varied greatly in transgenic chickens with different transgene insertion sites. The amount of HNP4 protein expressed in the eggs of G1 and G2 heterozygous transgenic chickens ranged from 1.65 μg/ml to 10.18 μg/ml. These results indicated that the production of transgenic chickens that expressed HNP4 protein in egg whites was successful.
Collapse
|
11
|
Ren X, Gong X, Cai Q, Guo X, Xu M, Ren Z, Zeng Y. Efficient stabilization of recombinant human coagulation factor VIII in the milk of transgenic mice using hFVIII and vWF co-expression vector transduction. Biotechnol Lett 2015; 37:1187-94. [PMID: 25700825 DOI: 10.1007/s10529-015-1793-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 02/10/2015] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To investigate the reasons for the instability of human coagulation factor FVIII (hFVIII) in milk which is an intractable obstacle during the hFVIII production by a transgenic mammary gland bioreactor. RESULTS We constructed P1A3-hFVIIIBDD and P1A3-hFVIIIBDD-IRES-vWF co-expression cassettes for generating transgenic mice. P1A3-hFVIII/CMV-vWF double heterozygotes were also prepared by mating P1A3-hFVIIIBDD with CMV-vWF mice. hFVIII bioactivity in milk was determined under different storage conditions. The half-life (in vitro) of hFVIII bioactivity in P1A3-hFVIIIBDD-IRES-vWF mice was significantly longer than P1A3-hFVIIIBDD mice [77 ± 4.9 vs. 44 ± 2.6 h at 4 °C, 32.5 ± 5 vs. 19.7 ± 0.6 h at room temperature and 7.4 ± 1.4 vs. 3.4 ± 0.6 at 37 °C, respectively (P < 0.05)]. The half-life (in vitro) of hFVIII bioactivity in milk of double heterozygotes was similar to P1A3-hFVIIIBDD-IRES-vWF ones, demonstrating that the vWF transgene expression in hFVIII transgenic mice can efficiently improve the stabilization of hFVIII bioactivity in milk. CONCLUSION We provide a new approach of P1A3-hFVIIIBDD-IRES-vWF co-expression to generate more stable hFVIII in transgenic milk with rapid and low cost as well as valuable information for producing pharmaceutical proteins by transgenic mammary gland bioreactor.
Collapse
Affiliation(s)
- Xiaoye Ren
- Shanghai Institute of Medical Genetics, Children's Hospital of Shanghai, Shanghai Jiao Tong University School of Medicine, Shanghai, 200040, China
| | | | | | | | | | | | | |
Collapse
|
12
|
Lin YS, Yang CC, Hsu CC, Hsu JT, Wu SC, Lin CJ, Cheng WTK. Establishment of a novel, eco-friendly transgenic pig model using porcine pancreatic amylase promoter-driven fungal cellulase transgenes. Transgenic Res 2014; 24:61-71. [PMID: 25063310 DOI: 10.1007/s11248-014-9817-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 07/11/2014] [Indexed: 11/25/2022]
Abstract
Competition between humans and livestock for cereal and legume grains makes it challenging to provide economical feeds to livestock animals. Recent increases in corn and soybean prices have had a significant impact on the cost of feed for pig producers. The utilization of byproducts and alternative ingredients in pig diets has the potential to reduce feed costs. Moreover, unlike ruminants, pigs have limited ability to utilize diets with high fiber content because they lack endogenous enzymes capable of breaking down nonstarch polysaccharides into simple sugars. Here, we investigated the feasibility of a transgenic strategy in which expression of the fungal cellulase transgene was driven by the porcine pancreatic amylase promoter in pigs. A 2,488 bp 5'-flanking region of the porcine pancreatic amylase gene was cloned by the genomic walking technique, and its structural features were characterized. Using GFP as a reporter, we found that this region contained promoter activity and had the potential to control heterologous gene expression. Transgenic pigs were generated by pronuclear microinjection. Founders and offspring were identified by PCR and Southern blot analyses. Cellulase mRNA and protein showed tissue-specific expression in the pancreas of F1 generation pigs. Cellulolytic enzyme activity was also identified in the pancreas of transgenic pigs. These results demonstrated the establishment of a tissue-specific promoter of the porcine pancreatic amylase gene. Transgenic pigs expressing exogenous cellulase may represent a way to increase the intake of low-cost, fiber-rich feeds.
Collapse
Affiliation(s)
- Y S Lin
- Department of Animal Science and Technology, National Taiwan University, Taipei, 106, Taiwan, ROC
| | | | | | | | | | | | | |
Collapse
|
13
|
Abstract
Hemophilia has evolved from an often fatal hereditary bleeding disorder to a disorder for which safe and effective treatment is available. However, there are several challenges remaining in the treatment of hemophilia. Prophylaxis to prevent bleeding is costly and requires frequent intravenous injections, which are cumbersome for patients. Venous access is often difficult to achieve, especially in small children where central venous lines may need to be implanted. Development of inhibitory antibodies makes treatment of acute bleeds difficult and prophylaxis in patients with inhibitors must also be better addressed. In order to improve treatment, new products are being developed, some of which are already in clinical trials. There are several approaches to prolonging half-lives such as PEGylation, Fc fusion and albumin fusion. Increased activity has been demonstrated in preclinical trials for factor IX and in a human trial with factor VII where the activity of the molecules has been increased by manipulation of the molecular composition. Additional approaches, including blockage of inhibitors of clotting, are also under investigation. Factor VIII and factor IX gene therapy have become a tangible possibility since phase I data recently have been published. Results are promising and there is hope that in the near future substantial progress will be made, perhaps making hemophilia the first genetic condition to be cured.
Collapse
Affiliation(s)
- Karin Knobe
- Malmö Centre for Thrombosis and Haemostasis, Skåne University Hospital, SE-205 02 Malmö, Sweden
| | | |
Collapse
|
14
|
Expression systems and species used for transgenic animal bioreactors. BIOMED RESEARCH INTERNATIONAL 2013; 2013:580463. [PMID: 23586046 PMCID: PMC3613084 DOI: 10.1155/2013/580463] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 01/15/2013] [Accepted: 02/17/2013] [Indexed: 01/05/2023]
Abstract
Transgenic animal bioreactors can produce therapeutic proteins with high value for pharmaceutical use. In this paper, we compared different systems capable of producing therapeutic proteins (bacteria, mammalian cells, transgenic plants, and transgenic animals) and found that transgenic animals were potentially ideal bioreactors for the synthesis of pharmaceutical protein complexes. Compared with other transgenic animal expression systems (egg white, blood, urine, seminal plasma, and silkworm cocoon), the mammary glands of transgenic animals have enormous potential. Compared with other mammalian species (pig, goat, sheep, and cow) that are currently being studied as bioreactors, rabbits offer many advantages: high fertility, easy generation of transgenic founders and offspring, insensitivity to prion diseases, relatively high milk production, and no transmission of severe diseases to humans. Noticeably, for a small- or medium-sized facility, the rabbit system is ideal to produce up to 50 kg of protein per year, considering both economical and hygienic aspects; rabbits are attractive candidates for the mammary-gland-specific expression of recombinant proteins. We also reviewed recombinant proteins that have been produced by targeted expression in the mammary glands of rabbits and discussed the limitations of transgenic animal bioreactors.
Collapse
|
15
|
A bioinformatic evaluation of potential allergenicity of 85 candidate genes in transgenic organisms. CHINESE SCIENCE BULLETIN-CHINESE 2012. [DOI: 10.1007/s11434-012-5149-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
16
|
Sun YL, Chang YS, Lin YS, Yen CH. Pilot production of recombinant human clotting factor IX from transgenic sow milk. J Chromatogr B Analyt Technol Biomed Life Sci 2012; 898:78-89. [PMID: 22578515 DOI: 10.1016/j.jchromb.2012.04.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 03/28/2012] [Accepted: 04/17/2012] [Indexed: 11/27/2022]
Abstract
Valuable pharmaceutical proteins produced from the mammary glands of transgenic livestock have potential use in the biomedical industry. In this study, recombinant human clotting factor IX (rhFIX) produced from transgenic sow milk for preclinical animal studies have been established. The transgenic sow milk was skimmed and treated with sodium phosphate buffer to remove abundant casein protein. Then, the γ-carboxylated rhFIX fraction was segregated through the Q Sepharose chromatography from uncarboxylated one. For safety issue, the process included virus inactivation by solvent/detergent (S/D) treatment. Subsequently, the S/D treated sample was loaded into the Heparin Sepharose column to recover the rhFIX fraction, which was then reapplied to the Heparin Sepharose column to enhance rhFIX purity and lower the ratio of activated form rhFIX (rhFIXa) easily. This was possible due to the higher affinity of the Heparin affinity sorbent for rhFIXa than for the rhFIX zymogen. Furthermore, an IgA removal column was used to eliminate porcine IgA in purified rhFIX. Finally, nanofiltration was performed for viral clearance. Consequently, a high-quality rhFIX product was produced (approximately 700 mg per batch). Other values for final rhFIX preparation were as follows: purity, >99%; average specific activity, 415.6±57.7 IU/mL and total milk impurity, <0.5 ng/mg. This is the first report that described the whole process and stable production of bioactive rhFIX from transgenic sow milk. The overall manufacturing process presented here has the potential for industrial production of rhFIX for treatment of hemophilia B patients.
Collapse
Affiliation(s)
- Yu-ling Sun
- Division of Biotechnology, Animal Technology Institute Taiwan, P.O. Box 23, Chunan 350, Miaoli, Taiwan, ROC
| | | | | | | |
Collapse
|
17
|
Abstract
Haemophilia care has undergone substantial improvements during the past 40-50 years. Early clotting factor concentrates were not sufficiently refined to enable self-administered treatment at home until the 1970s. Unfortunately, these advances led to transmission of viral diseases including HIV and hepatitis, resulting in an increased burden of morbidity and mortality, especially during the 1980s. Throughout the past two decades, product development, including the advent of recombinant concentrates, has greatly improved the safety and availability of therapy and the focus of care is shifting towards prevention and management of disease sequelae. Long-term substitution therapy (prophylaxis) of the missing clotting factor is the recommended treatment in severe haemophilia, but several research issues remain to be elucidated such as when to start and how to optimise these regimens, and when or whether to stop this expensive treatment. The major side-effect of treatment, development of inhibitors to the infused concentrate, is the main threat to the health of patients and consequently the goal of intense research. Development of new products with improved pharmacokinetics is the next step to improved therapy.
Collapse
Affiliation(s)
- Erik Berntorp
- Lund University, Malmö Centre for Thrombosis and Haemostasis, Skåne University Hospital, Malmö, Sweden.
| | | |
Collapse
|
18
|
Tan WS, Carlson DF, Walton MW, Fahrenkrug SC, Hackett PB. Precision editing of large animal genomes. ADVANCES IN GENETICS 2012; 80:37-97. [PMID: 23084873 PMCID: PMC3683964 DOI: 10.1016/b978-0-12-404742-6.00002-8] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Transgenic animals are an important source of protein and nutrition for most humans and will play key roles in satisfying the increasing demand for food in an ever-increasing world population. The past decade has experienced a revolution in the development of methods that permit the introduction of specific alterations to complex genomes. This precision will enhance genome-based improvement of farm animals for food production. Precision genetics also will enhance the development of therapeutic biomaterials and models of human disease as resources for the development of advanced patient therapies.
Collapse
Affiliation(s)
- Wenfang Spring Tan
- Center for Genome Engineering, University of Minnesota, Minneapolis, MN, USA
| | | | | | | | | |
Collapse
|
19
|
Pipe SW, Miao H, Butler SP, Calcaterra J, Velander WH. Functional factor VIII made with von Willebrand factor at high levels in transgenic milk. J Thromb Haemost 2011; 9:2235-42. [PMID: 21920013 PMCID: PMC3444248 DOI: 10.1111/j.1538-7836.2011.04505.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Current manufacturing methods for recombinant human factor VIII (rFVIII) within mammalian cell cultures are inefficient, hampering the production of sufficient amounts for affordable, worldwide treatment of hemophilia A. However, rFVIII has been expressed at very high levels by the transgenic mammary glands of mice, rabbits, sheep, and pigs. Unfortunately, it is secreted into milk with low specific activity, owing in part to the labile, heterodimeric structure that results from furin processing of its B domain. OBJECTIVES To express biologically active rFVIII in the milk of transgenic mice through targeted bioengineering. METHODS Transgenic mice were made with a mammary-specific FVIII gene (226/N6) bioengineered for efficient expression and stability, encoding a protein containing a B domain with no furin cleavage sites. 226/N6 was expressed with and without von Willebrand factor (VWF). 226/N6 was evaluated by ELISA, SDS-PAGE, western blot, and one-stage and two-stage clotting assays. The hemostatic activity of immunoaffinity-enriched 226/N6 was studied in vivo by infusion into hemophilia A knockout mice. RESULTS AND CONCLUSIONS With or without coexpression of VWF, 226/N6 was secreted into milk as a biologically active single-chain molecule that retained high specific activity, similar to therapeutic-grade FVIII. 226/N6 had > 450-fold higher IU mL(-1) than previously reported in cell culture for rFVIII. 226/N6 exhibited similar binding to plasma-derived VWF as therapeutic-grade rFVIII, and intravenous infusion of transgenic 226/N6 corrected the bleeding phenotype of hemophilia A mice. This provides proof-of-principle for the study of expression of 226/N6 and perhaps other single-chain bioengineered rFVIIIs in the milk of transgenic livestock.
Collapse
Affiliation(s)
- Steven W. Pipe
- Department of Pediatrics, University of Michigan, Ann Arbor, MI
| | - Hongzhi Miao
- Department of Pediatrics, University of Michigan, Ann Arbor, MI
| | - Stephen P. Butler
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA
| | - Jennifer Calcaterra
- Department of Chemical & Biomolecular Engineering, University of Nebraska, Lincoln, NE
| | - William H. Velander
- Department of Chemical & Biomolecular Engineering, University of Nebraska, Lincoln, NE
| |
Collapse
|
20
|
Whyte JJ, Prather RS. Genetic modifications of pigs for medicine and agriculture. Mol Reprod Dev 2011; 78:879-91. [PMID: 21671302 PMCID: PMC3522184 DOI: 10.1002/mrd.21333] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Accepted: 05/09/2011] [Indexed: 12/18/2022]
Abstract
Genetically modified swine hold great promise in the fields of agriculture and medicine. Currently, these swine are being used to optimize production of quality meat, to improve our understanding of the biology of disease resistance, and to reduced waste. In the field of biomedicine, swine are anatomically and physiologically analogous to humans. Alterations of key swine genes in disease pathways provide model animals to improve our understanding of the causes and potential treatments of many human genetic disorders. The completed sequencing of the swine genome will significantly enhance the specificity of genetic modifications, and allow for more accurate representations of human disease based on syntenic genes between the two species. Improvements in both methods of gene alteration and efficiency of model animal production are key to enabling routine use of these swine models in medicine and agriculture.
Collapse
Affiliation(s)
- Jeffrey J. Whyte
- National Swine Resource and Research Center, University of Missouri, Columbia, MO, U.S.A
- Department of Biomedical Sciences, University of Missouri, Columbia, MO, U.S.A
- Division of Animal Science, University of Missouri, Columbia, MO, U.S.A
| | - Randall S. Prather
- National Swine Resource and Research Center, University of Missouri, Columbia, MO, U.S.A
- Division of Animal Science, University of Missouri, Columbia, MO, U.S.A
| |
Collapse
|
21
|
Transgenic mammalian species, generated by somatic cell cloning, in biomedicine, biopharmaceutical industry and human nutrition/dietetics--recent achievements. Pol J Vet Sci 2011; 14:317-28. [PMID: 21721422 DOI: 10.2478/v10181-011-0050-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Somatic cell cloning technology in mammals promotes the multiplication of productively-valuable genetically engineered individuals, and consequently allows also for standardization of transgenic farm animal-derived products, which, in the context of market requirements, will have growing significance. Gene farming is one of the most promising areas in modern biotechnology. The use of live bioreactors for the expression of human genes in the lactating mammary gland of transgenic animals seems to be the most cost-effective method for the production/processing of valuable recombinant therapeutic proteins. Among the transgenic farm livestock species used so far, cattle, goats, sheep, pigs and rabbits are useful candidates for the expression of tens to hundreds of grams of genetically-engineered proteins or xenogeneic biopreparations in the milk. At the beginning of the new millennium, a revolution in the treatment of disease is taking shape due to the emergence of new therapies based on recombinant human proteins. The ever-growing demand for such pharmaceutical or nutriceutical proteins is an important driving force for the development of safe and large-scale production platforms. The aim of this paper is to present an overall survey of the state of the art in investigations which provide the current knowledge for deciphering the possibilities of practical application of the transgenic mammalian species generated by somatic cell cloning in biomedicine, the biopharmaceutical industry, human nutrition/dietetics and agriculture.
Collapse
|
22
|
The possibilities of practical application of transgenic mammalian species generated by somatic cell cloning in pharmacology, veterinary medicine and xenotransplantology. Pol J Vet Sci 2011; 14:329-40. [DOI: 10.2478/v10181-011-0051-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
23
|
Comprehensive characterization of the site-specific N-glycosylation of wild-type and recombinant human lactoferrin expressed in the milk of transgenic cloned cattle. Glycobiology 2010; 21:206-24. [DOI: 10.1093/glycob/cwq151] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
24
|
Detection and genotyping of porcine circovirus in naturally infected pigs by oligo-microarray. Res Vet Sci 2010; 89:133-9. [DOI: 10.1016/j.rvsc.2010.01.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2007] [Revised: 01/11/2010] [Accepted: 01/14/2010] [Indexed: 11/22/2022]
|
25
|
|
26
|
He Z, Zhao Y, Mei G, Li N, Chen Y. Could protein tertiary structure influence mammary transgene expression more than tissue specific codon usage? Transgenic Res 2010; 19:519-33. [PMID: 20563642 PMCID: PMC2902731 DOI: 10.1007/s11248-010-9411-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2009] [Accepted: 05/19/2010] [Indexed: 12/03/2022]
Abstract
Animal mammary glands have been successfully employed to produce therapeutic recombinant human proteins. However, considerable variation in animal mammary transgene expression efficiency has been reported. We now consider whether aspects of codon usage and/or protein tertiary structure underlie this variation in mammary transgene expression.
Collapse
Affiliation(s)
- Zuyong He
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, 510006, Guangzhou, People's Republic of China
| | | | | | | | | |
Collapse
|
27
|
LEE HG, LEE HC, KIM SW, LEE P, CHUNG HJ, LEE YK, HAN JH, HWANG IS, YOO JI, KIM YK, KIM HT, LEE HT, CHANG WK, PARK JK. Production of Recombinant Human Von Willebrand Factor in the Milk of Transgenic Pigs. J Reprod Dev 2009; 55:484-90. [DOI: 10.1262/jrd.20212] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Hyun-Gi LEE
- National Institute of Animal Science, RDA
- Animal Resources Research Center, Kon-Kuk University
| | | | | | | | | | | | | | | | | | | | | | - Hoon-Taek LEE
- Animal Resources Research Center, Kon-Kuk University
| | | | | |
Collapse
|
28
|
Lee P, Chung HK, Lee HG, Lee HC, Woo JS, Lee S, Jo SJ, Chang WK, Lee HT, Kwon M, Park JK. Cloning and characterization of 5'-untranslated region of porcine beta casein gene (CSN2). Domest Anim Endocrinol 2008; 35:245-53. [PMID: 18583090 DOI: 10.1016/j.domaniend.2008.04.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Revised: 04/23/2008] [Accepted: 04/24/2008] [Indexed: 10/22/2022]
Abstract
beta-Casein (CSN2) is a major milk protein in most mammals. The CSN2 gene is generally induced by lactogenic hormones bound to its promoter. The expression of this gene can be enhanced by signal transducers and activators of transcription (STAT) and glucocorticoid receptor (GR). Here, we analyzed the promoter and intron 1 regions of the porcine CSN2 gene. The porcine CSN2 promoter and intron 1 regions (-3098bp to +2446bp) were cloned into the pGL3-Basic vector containing the luciferase reporter gene (pCSN2-PEI). Lactogenic signals induced the transcription of porcine CSN2. By using AG490, a Janus kinase (JAK) inhibitor, we demonstrated that STAT5 positively regulates the transcription of porcine CSN2. Further, seven STAT mutants were generated by site-directed mutagenesis. By performing electrophoretic mobility shift assays (EMSAs), we located a critical element for pCSN2-PEI transcription bound to STAT5 in the -102bp to -84bp region. The construct containing only the promoter region (pCSN2-P), however, did not exert any promotive effects on transcription in two cell types-a mouse mammary epithelial cell line (HC11) and porcine mammary gland epithelial cells (PMECs). Thus, the construct containing intron 1 of porcine CSN2 exerts an elevating effect on transcription. We suggest that the transcription of porcine CSN2 is regulated by lactogenic signals via the STAT5 site (-102bp to -84bp) and intron 1.
Collapse
Affiliation(s)
- Poongyeon Lee
- Animal Biotechnology Division, National Institute of Animal Science, RDA, Suwon, Republic of Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Park KW, Choi KM, Hong SP, Han GS, Yoo JY, Jin DI, Seol JG, Park CS. Production of transgenic recloned piglets harboring the human granulocyte-macrophage colony stimulating factor (hGM-CSF) gene from porcine fetal fibroblasts by nuclear transfer. Theriogenology 2008; 70:1431-8. [PMID: 18804273 DOI: 10.1016/j.theriogenology.2008.03.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2007] [Revised: 02/18/2008] [Accepted: 03/12/2008] [Indexed: 11/18/2022]
Abstract
We used nuclear transfer (NT) to develop transgenic female pigs harboring goat beta-casein promoter/human granulocyte-macrophage colony stimulating factor (hGM-CSF). The expression of hGM-CSF was specific to the mammary gland, and the glycosylation-derived size heterogeneity corresponded to that of the native human protein. Although various cell types have been used to generate cloned animals, little is currently known about the potential use of fibroblasts derived from a cloned fetus as donor cells for nuclear transfer. The developmental potential of porcine cloned fetal fibroblasts transfected with hGM-CSF was evaluated in the present study. Cloned fetal fibroblasts were isolated from a recipient following the transplantation of NT embryos. The cells were transfected with both hGM-CSF and the neomycin resistance gene in order to be used as donor cells for NT. Reconstructed embryos were implanted into six sows during estrus; two of the recipient sows delivered seven healthy female piglets with the hGM-CSF gene (confirmed with PCR and fluorescent in situ hybridization) and microsatellite analysis confirmed that the clones were genetically identical to the donor cells. The expression of hGM-CSF was strong in the mammary glands of a transgenic pig that died a few days prior to parturition (110 d after AI). These results demonstrated that somatic cells derived from a cloned fetus can be used to produce recloned and transgenic pigs.
Collapse
Affiliation(s)
- K W Park
- MGEN, Inc., #1101 World Meridian Venture Center, 60-24 Gasan-Dong, Guemchun-Gu, Seoul 153-781, Republic of Korea.
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Chrenek P, Trandzik J, Massanyi P, Makarevich A, Lukac N, Peskovicova D, Paleyanda R. Effect of transgenesis on reproductive traits of rabbit males. Anim Reprod Sci 2008; 99:127-34. [PMID: 16766146 DOI: 10.1016/j.anireprosci.2006.04.052] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2005] [Revised: 01/13/2006] [Accepted: 04/18/2006] [Indexed: 11/25/2022]
Abstract
The influence of foreign transgene integration on the reproductive capabilities of rabbit males is not known. Therefore, we analyzed their ejaculate characteristics, reproductive capabilities, occurrence of pathological spermatozoa and histological structure of the testis. We have generated transgenic rabbits by microinjection of WAP-hFVIII gene into pronucleus of fertilized egg. We observed that the libido, volume and pH value of the ejaculate did not differ significantly between transgenic and non-transgenic male lines. The motility, concentration, osmolarity, thermoresistant test of spermatozoa (at 1 or 6 h) and the percentage of alive spermatozoa were significantly different (p < 0.001) among transgenic and non-transgenic males. No significant differences were found between transgenic and non-transgenic male lines in the occurrence of pathological spermatozoa and histology of the testis. The ability of spermatozoa from transgenic and non-transgenic males to fertilize eggs was ranged within 96 and 100%; while the yield of transgenic embryos ranged from 43 to 57%. Our results show that mammary gland specific over-expression mWAP-hFVIII gene construct does not affect reproductive traits of transgenic rabbit males.
Collapse
Affiliation(s)
- Peter Chrenek
- Slovak Agricultural Research Centre, Nitra, Slovak Republic.
| | | | | | | | | | | | | |
Collapse
|
31
|
Efficient recovery of recombinant human erythropoietin from milk of transgenic pigs by two-step pretreatment. BIOTECHNOL BIOPROC E 2008. [DOI: 10.1007/s12257-007-0158-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
32
|
Monosialylated biantennary N-glycoforms containing GalNAc–GlcNAc antennae predominate when human EPO is expressed in goat milk. Arch Biochem Biophys 2008; 470:163-75. [DOI: 10.1016/j.abb.2007.11.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Revised: 11/27/2007] [Accepted: 11/29/2007] [Indexed: 11/22/2022]
|
33
|
Bösze Z, Baranyi M, Whitelaw CBA. Producing recombinant human milk proteins in the milk of livestock species. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 606:357-93. [PMID: 18183938 DOI: 10.1007/978-0-387-74087-4_15] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Abstract
Recombinant human proteins produced by the mammary glands of genetically modified transgenic livestock mammals represent a special aspect of milk bioactive components. For therapeutic applications, the often complex posttranslational modifications of human proteins should be recapitulated in the recombinant products. Compared to alternative production methods, mammary gland production is a viable option, underlined by a number of transgenic livestock animal models producing abundant biologically active foreign proteins in their milk. Recombinant proteins isolated from milk have reached different phases of clinical trials, with the first marketing approval for human therapeutic applications from the EMEA achieved in 2006.
Collapse
|
34
|
Abstract
Swine production has been an important part of our lives since the late Mesolithic or early Neolithic periods, and ranks number one in world meat production. Pig production also contributes to high-value-added medical markets in the form of pharmaceuticals, heart valves, and surgical materials. Genetic engineering, including the addition of exogenous genetic material or manipulation of the endogenous genome, holds great promise for changing pig phenotypes for agricultural and medical applications. Although the first transgenic pigs were described in 1985, poor survival of manipulated embryos; inefficiencies in the integration, transmission, and expression of transgenes; and expensive husbandry costs have impeded the widespread application of pig genetic engineering. Sequencing of the pig genome and advances in reproductive technologies have rejuvenated efforts to apply transgenesis to swine. Pigs provide a compelling new resource for the directed production of pharmaceutical proteins and the provision of cells, vascular grafts, and organs for xenotransplantation. Additionally, given remarkable similarities in the physiology and size of people and pigs, swine will increasingly provide large animal models of human disease where rodent models are insufficient. We review the challenges facing pig transgenesis and discuss the utility of transposases and recombinases for enhancing the success and sophistication of pig genetic engineering. 'The paradise of my fancy is one where pigs have wings.' (GK Chesterton).
Collapse
Affiliation(s)
- Karl J Clark
- Department of Animal Science at the University of Minnesota, Fitch Ave, St, Paul, MN 55108, USA
| | | | | |
Collapse
|
35
|
Prather RS. Nuclear remodeling and nuclear reprogramming for making transgenic pigs by nuclear transfer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 591:1-13. [PMID: 17176551 DOI: 10.1007/978-0-387-37754-4_1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A better understanding of the cellular and molecular events that occur when a nucleus is transferred to the cytoplasm of an oocyte will permit the development of improved procedures for performing nuclear transfer and cloning. In some cases it appears that the gene(s) are reprogrammed, while in other cases there appears to be little effect on gene expression. Not only does the pattern of gene expression need to be reprogrammed, but other structures within the nucleus also need to be remodeled. While nuclear transfer works and transgenic and knockout animals can be created, it still is an inefficient process. However, even with the current low efficiencies this technique has proved very valuable for the production of animals that might be useful for tissue or organ transplantation to humans.
Collapse
Affiliation(s)
- Randall S Prather
- Division of Animal Science, Food for the 21st Century, College of Food, Agriculture & Natural Resources, University of Missouri-Columbia, 920 East Campus Drive, E125 ASRC, Columbia, Missouri 65211-5300, USA.
| |
Collapse
|
36
|
Abstract
Although up to 80% of high-responding inhibitors in patients with severe factor VIII deficiency can be eliminated using heterogeneous regimens for immune tolerance induction, the residual morbidity in this population of haemophilic patients is far from trivial. There is an exigent need for focussed basic, translational and clinical research to extend our understanding of the pathogenesis of haemophilic inhibitor development. In this article, we identify four key research needs, including (i) whether presently available clotting factor concentrates (CFCs) have differential antigenicity, giving rise to clinically relevant immunogenicity; (ii) the interplay of quantitative and qualitative (e.g. age at first exposure) influences of CFCs as well as host-environmental factors (e.g. vaccination effects) on inhibitor development; (iii) the therapeutic role (if any) that concurrent immune tolerance with suppressive or immune-competitive therapeutic strategies play in inhibitor eradication and (iv) pending any major therapeutic advances, alternative or enhanced strategies for treating acute haemorrhage and for preventing chronic haemorrhagic events in these patients.
Collapse
Affiliation(s)
- W K Hoots
- Gulf States Hemophilia and Thrombophilia Center, The University of Texas Health Science Center, Houston, TX 77030, USA.
| |
Collapse
|
37
|
Melo EO, Canavessi AMO, Franco MM, Rumpf R. Animal transgenesis: state of the art and applications. J Appl Genet 2007; 48:47-61. [PMID: 17272861 DOI: 10.1007/bf03194657] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
There is a constant expectation for fast improvement of livestock production and human health care products. The advent of DNA recombinant technology and the possibility of gene transfer between organisms of distinct species, or even distinct phylogenic kingdoms, has opened a wide range of possibilities. Nowadays we can produce human insulin in bacteria or human coagulation factors in cattle milk. The recent advances in gene transfer, animal cloning, and assisted reproductive techniques have partly fulfilled the expectation in the field of livestock transgenesis. This paper reviews the recent advances and applications of transgenesis in livestock and their derivative products. At first, the state of art and the techniques that enhance the efficiency of livestock transgenesis are presented. The consequent reduction in the cost and time necessary to reach a final product has enabled the multiplication of transgenic prototypes around the world. We also analyze here some emerging applications of livestock transgenesis in the field of pharmacology, meat and dairy industry, xenotransplantation, and human disease modeling. Finally, some bioethical and commercial concerns raised by the transgenesis applications are discussed.
Collapse
Affiliation(s)
- Eduardo O Melo
- EMBRAPA Genetic Resources and Biotechnology, Av. W/5, Norte Final, PBI, Sala 7B, Brasilia, DF, Brazil, CEP 70770-900.
| | | | | | | |
Collapse
|
38
|
Chrenek P, Ryban L, Vetr H, Makarevich AV, Uhrin P, Paleyanda RK, Binder BR. Expression of recombinant human factor VIII in milk of several generations of transgenic rabbits. Transgenic Res 2007; 16:353-61. [PMID: 17265165 DOI: 10.1007/s11248-007-9070-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2006] [Accepted: 01/08/2007] [Indexed: 11/30/2022]
Abstract
Transgenic founder rabbits carrying a gene construct consisting of a 2.5 kb murine whey acidic protein promoter (mWAP), 7.2 kb of the human clotting factor VIII (hFVIII) cDNA and 4.6 kb of 3' flanking sequences of mWAP gene were crossed for three generations. All transgenic animals showed stable transgene transmission. Transgenic females showed high level of recombinant hFVIII (rhFVIII) mRNA expression in biopsed mammary gland tissues, while marginal expression of rhFVIII mRNA was observed in the spleen, lung and brain. No adverse effects of ectopic expression on the physiology of the rabbits were observed. Expression was not detected in the liver, kidney, heart and skeletal muscle. In transgenic females derived from three generations, rhFVIII protein was secreted from the mammary gland of lactating females, as shown by Western blotting. Biological activity of rhFVIII protein, as revealed in clotting assays was ranged from 0.012 to 0.599 IU/ml corresponding to 1.2% and 59.9% of the hFVIII level in normal human plasma. No apparent effect of secreted rhFVIII on the milk performance of rabbits was observed. Our results confirm the possibility of producing a significant amount of a biologically active rhFVIII in the mammary gland of established transgenic rabbit lines.
Collapse
Affiliation(s)
- Peter Chrenek
- Slovak Agricultural Research Centre, Nitra, Slovak Republic.
| | | | | | | | | | | | | |
Collapse
|
39
|
Dragin S, Pivko J, Massanyi P, Lukac N, Makarevich AV, Paleyanda RK, Chrenek P. Ultrastructural Morphometry of Mammary Gland in Transgenic and Non-transgenic Rabbits. Anat Histol Embryol 2006; 35:351-6. [PMID: 17156086 DOI: 10.1111/j.1439-0264.2006.00692.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mammary gland of transgenic animals has been used for the production of recombinant proteins of therapeutic and nutraceutical use. The objective of this study was to compare the ultrastructure of transgenic and non-transgenic rabbit mammary gland tissue. New Zealand White transgenic rabbits were obtained by breeding non-transgenic rabbits with transgenic founder rabbits containing a whey acidic protein-human factor VIII (WAP-hFVIII) transgene integrated into their genome. Samples of mammary gland tissue from lactating rabbit females were isolated by surgical procedures. These samples were examined by optical and electron microscopy and photographs were taken. Measurements of ultrastructural organelles were made from digital images of the mammary cells. No differences were found in the cellular structure of mammary tissue, but significant differences t((0.001)) in the relative volume of mitochondria and vacuoles between transgenic and non-transgenic mammary gland epithelium were observed.
Collapse
Affiliation(s)
- S Dragin
- Slovak Agricultural Research Authority, Nitra, Slovak Republic
| | | | | | | | | | | | | |
Collapse
|
40
|
Malenko GP, Prokof’ev MI, Pinyugina MV, Antipova TA, Mezina MN, Bukreev YM. Production of cloned bovine embryos by somatic cell transfer into enucleated zona-free oocytes. BIOL BULL+ 2006. [DOI: 10.1134/s1062359006030034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
41
|
Park JK, Lee YK, Lee P, Chung HJ, Kim S, Lee HG, Seo MK, Han JH, Park CG, Kim HT, Kim YK, Min KS, Kim JH, Lee HT, Chang WK. Recombinant human erythropoietin produced in milk of transgenic pigs. J Biotechnol 2006; 122:362-71. [PMID: 16460825 DOI: 10.1016/j.jbiotec.2005.11.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2005] [Revised: 11/21/2005] [Accepted: 11/29/2005] [Indexed: 11/22/2022]
Abstract
We have developed a line of transgenic swine harboring recombinant human erythropoietin through microinjection into fertilized one cell pig zygotes. Milk from generations F1 and F2 transgenic females was analyzed, and hEPO was detected in milk from all lactating females at concentrations of approximately 877.9+/-92.8 IU/1 ml. The amino acid sequence of rhEPO protein in the transgenic pig milk matched that of commercial rhEPO produced from cultured animal cells. In addition, an F-36 cell line, which proliferates in the presence of hEPO or commercial EPO, was induced to synthesize erythroid by extracts from tg sow milk. This study provides evidence that production of purified rhEPO from transgenic pig milk is a potentially valuable technology, and can be used as a cost-effective alternative in clinical applications as well as providing other clinical advantages.
Collapse
Affiliation(s)
- Jin-Ki Park
- Animal Biotechnology Division, National Livestock Research Institute, Suwon 441-706, Republic of Korea
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Chrenek P, Vasicek D, Makarevich AV, Jurcik R, Suvegova K, Parkanyi V, Bauer M, Rafay J, Batorova A, Paleyanda RK. Increased transgene integration efficiency upon microinjection of DNA into both pronuclei of rabbit embryos. Transgenic Res 2005; 14:417-28. [PMID: 16201408 DOI: 10.1007/s11248-005-3238-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Transgenic rabbits provide a useful biological model for the study of the regulation of mammalian genes. However, transgene integration efficiency has generally been low. Here we present a first attempt to increase the integration rate of exogenous DNA into the rabbit genome, using a double pronuclei microinjection method. Pronuclear stage rabbit embryos were recovered from superovulated NZW females, 19-20 h after hCG injection. About 5 microg/mL of exogenous DNA solution was microinjected either into one pronucleus (single microinjection, SM) or into both pronuclei (double microinjected, DM). The transgene consisted of a 2.5 kb murine whey acidic protein promoter (mWAP), 7.2 kb cDNA of the human clotting factor VIII (hFVIII), and 4.6 kb that of 3' flanking sequences of the mWAP gene. The in vitro survival of DM embryos to the blastocyst stage was lower than that of SM embryos (68 vs. 89%). Similar results were obtained using EGFP as a control gene construct. However, there was no difference in the percentage of embryos that developed into live offspring using DM (25%) vs. SM (26%). The integration frequency of mWAP-hFVIII into the genome of transgenic rabbits was 3.3% (1/30) upon SM and 8.1% (4/49) at DM (p < 0.05). All founders transmitted the transgene to their offspring in a Mendelian fashion. The SM founder female secreted 87.4 microg/mL rhFVIII in milk, with an activity of 0.594 IU/mL. The DM founder female produced 118 microg/mL rhFVIII, with activity values of 18 IU/ mL. This is the first report of transgenic rabbit production using a double microinjection technique. Our preliminary results suggest that this method can increase the efficiency of production of transgenic rabbit founders, giving a higher integration rate than single microinjection.
Collapse
Affiliation(s)
- Peter Chrenek
- Research Institute of Animal Production, Hlohovská 2, 949 92 Nitra, Slovak Republic.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Abstract
The past 10 years of clinical experience have demonstrated the safety and efficacy of recombinant clotting factors. With the adoption of prophylactic strategies, there has been considerable progress in avoiding the complications of hemophilia. Now, insights from our understanding of clotting factor structure and function, mechanisms of hemophilia and inhibitors, gene therapy advances and a worldwide demand for clotting factor concentrates leave us on the brink of embracing targeted bioengineering strategies to further improve hemophilia therapeutics. The ability to bioengineer recombinant clotting factors with improved function holds promise to overcome some of the limitations in current treatment, the high costs of therapy and increase availability to a broader world hemophilia population. Most research has been directed at overcoming the inherent limitations of rFVIII expression and the inhibitor response. This includes techniques to improve rFVIII biosynthesis and secretion, functional activity, half-life and antigenicity/immunogenicity. Some of these proteins have already reached commercialization and have been utilized in gene therapy strategies, while others are being evaluated in pre-clinical studies. These novel proteins partnered with advances in gene transfer vector design and delivery may ultimately achieve persistent expression of FVIII leading to an effective long-term treatment strategy for hemophilia A. In addition, these novel FVIII proteins could be partnered with new advances in alternative recombinant protein production in transgenic animals yielding an affordable, more abundant supply of rFVIII. Novel rFIX proteins are being considered for gene therapy strategies whereas novel rVIIa proteins are being evaluated to improve the potency and extend their plasma half-life. This review will summarize the status of current recombinant clotting factors and the development and challenges of recombinant clotting factors bioengineered for improved function.
Collapse
Affiliation(s)
- S W Pipe
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI 48109, USA.
| |
Collapse
|
44
|
Abstract
In the 20th century, haemophilia evolved from a life-threatening, crippling disease to one for which the prognosis is excellent and many patients lead normal, productive lives. Although dramatic achievements in the treatment of haemophilia have occurred, the current therapies have significant drawbacks. Among these is the relatively high incidence of inhibitor development, the requirement for frequent intravenous infusions to prevent bleeding complications, the lack of effective treatment for established joint disease, and the high cost of treatment. The future goal of haemophilia treatment first and foremost is curing this genetic condition via gene therapy. As this goal is likely many years away, improvements in the current factor products in order to reduce the development of inhibitors and to reduce the frequency of therapy are more immediately achievable goals. Finally, improving the treatment of bleeding complications, particularly in inhibitor patients, and developing novel adjunctive therapies for the management of joint disease are also important goals for the near future. This review will discuss in detail the cu-rrent and future goals of haemophilia therapy.
Collapse
Affiliation(s)
- Guy Young
- Children's Hospital of Orange County, 455 S. Main Street, Orange, CA 92868, USA.
| | | |
Collapse
|
45
|
Van Cott KE, Monahan PE, Nichols TC, Velander WH. Haemophilic factors produced by transgenic livestock: abundance that can enable alternative therapies worldwide. Haemophilia 2005; 10 Suppl 4:70-6. [PMID: 15479375 PMCID: PMC3925420 DOI: 10.1111/j.1365-2516.2004.00983.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Haemophilia replacement factors, both plasma-derived and recombinant, are in relatively short supply and are high-cost products. This has stymied the study and development of alternative methods of administration of haemophilia therapy even in the most economically advanced countries, owing to the large amounts of material needed because bioabsorption and bioavailability of haemophilic factors can be less than 10% when using non-intravenous routes of delivery. There is therefore a need to increase access to therapy worldwide by decreasing the cost and increasing the abundance so that therapy can be achieved through simplified, alternative delivery methods. Transgenic livestock have been used to produce haemophilic factors in milk. Only the pig mammary gland has been shown to carry out the post-translational processing necessary to enable both the biological activity and long circulation half-life needed for therapeutic glycoproteins. Furthermore, the large amounts of recombinant protein that can be produced from pig milk make feasible the use of alternative delivery methods such as oral, intratracheal, subcutaneous, and intramuscular administration.
Collapse
|
46
|
Van Cott KE, Velander WH. Transgenic animals as drug factories: a new source of recombinant protein therapeutics. Expert Opin Investig Drugs 2005; 7:1683-90. [PMID: 15991910 DOI: 10.1517/13543784.7.10.1683] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The utility of transgenic animal bioreactors for the production of complex therapeutic proteins is based on lower production costs, higher production capacities and safer, pathogen free products. Until gene therapy becomes broadly efficacious, transgenic-derived therapeutics are the most attractive alternative for prophylactic, replacement therapy in genetic disorders, such as haemophilia. Many other disease states need short-term treatment of significant amounts of recombinant proteins that could be made amply available from transgenic animal sources. In addition, transgenic animals will provide an ideal expression system for the production of a portfolio of alternative therapeutics for patient populations developing inhibiting antibodies, for enhanced bioactivity, or for increased plasma clearance times. The FDA approval of a transgenic-derived therapeutic is still pending, but a review of Phase I & II data from antithrombin III from goat milk is encouraging, and companies are continuing to add potential therapeutics to their product pipeline.
Collapse
Affiliation(s)
- K E Van Cott
- Pharmaceutical Engineering Institute, Department of Chemical Engineering, Virginia Tech, Blacksburg, VA 24061, USA
| | | |
Collapse
|
47
|
Hwang G, Müller F, Rahman MA, Williams DW, Murdock PJ, Pasi KJ, Goldspink G, Farahmand H, Maclean N. Fish as bioreactors: transgene expression of human coagulation factor VII in fish embryos. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2004; 6:485-492. [PMID: 15129328 DOI: 10.1007/s10126-004-3121-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2003] [Accepted: 02/11/2004] [Indexed: 05/24/2023]
Abstract
A plasmid containing human coagulation factor VII (hFVII) complementary DNA regulated by a cytomegalovirus promoter was microinjected into fertilized eggs of zebrafish, African catfish, and tilapia. The active form of hFVll was detected in the fish embryos by various assays. This positive expression of human therapeutic protein in fish embryos demonstrates the possibility of exploitation of transgenic fish as bioreactors.
Collapse
Affiliation(s)
- Gyulin Hwang
- Division of Cell Sciences, School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton, SO16 7PX, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Huang C, Hung JJ, Wu CY, Chien MS. Multiplex PCR for rapid detection of pseudorabies virus, porcine parvovirus and porcine circoviruses. Vet Microbiol 2004; 101:209-14. [PMID: 15223125 DOI: 10.1016/j.vetmic.2004.04.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2002] [Revised: 01/20/2004] [Accepted: 04/29/2004] [Indexed: 11/30/2022]
Abstract
A multiplex PCR (mPCR) assay was developed and subsequently evaluated for its effectiveness as a means to simultaneously detect multiple viral infections of swine. Specific primers for each of four common DNA viruses, namely, pseudorabies virus (PRV), porcine circovirus type I (PCV1), porcine circovirus type II (PCV2), and porcine parvovirus (PPV), were used for testing procedure. The assay was shown to be highly sensitive in that as little as 10(-4) ng of each of the respective amplicons (approximately equal to 10,000 molecules) was detected when a composite of all four viruses (including both field and gene-deleted permutations of PRV) was tested as a single sample. It was also effective for detecting one or more of these same viruses in various combinations in specimens including lymph nodes, lungs, spleens, and tonsils collected from clinically ill pigs, and in specimens in spleen collected from aborted fetuses. The relative efficiency (compared to performing separate assays for each virus) and apparent sensitivity of mPCR suggest its potential application for routine molecular diagnostic purposes.
Collapse
Affiliation(s)
- Chienjin Huang
- Graduate Institute of Veterinary Microbiology, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan, ROC.
| | | | | | | |
Collapse
|
49
|
Bosze Z, Hiripi L, Carnwath JW, Niemann H. The transgenic rabbit as model for human diseases and as a source of biologically active recombinant proteins. Transgenic Res 2004; 12:541-53. [PMID: 14601653 DOI: 10.1023/a:1025816809372] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Until recently, transgenic rabbits were produced exclusively by pronuclear microinjection which results in additive random insertional transgenesis; however, progress in somatic cell cloning based on nuclear transfer will soon make it possible to produce rabbits with modifications to specific genes by the combination of homologous recombination and subsequent prescreening of nuclear donor cells. Transgenic rabbits have been found to be excellent animal models for inherited and acquired human diseases including hypertrophic cardiomyopathy, perturbed lipoprotein metabolism and atherosclerosis. Transgenic rabbits have also proved to be suitable bioreactors for the production of recombinant protein both on an experimental and a commercial scale. This review summarizes recent research based on the transgenic rabbit model.
Collapse
Affiliation(s)
- Zs Bosze
- Department of Animal Biology, Agricultural Biotechnology Center Gödöllo, Hungary.
| | | | | | | |
Collapse
|
50
|
Van den Hout JMP, Kamphoven JHJ, Winkel LPF, Arts WFM, De Klerk JBC, Loonen MCB, Vulto AG, Cromme-Dijkhuis A, Weisglas-Kuperus N, Hop W, Van Hirtum H, Van Diggelen OP, Boer M, Kroos MA, Van Doorn PA, Van der Voort E, Sibbles B, Van Corven EJJM, Brakenhoff JPJ, Van Hove J, Smeitink JAM, de Jong G, Reuser AJJ, Van der Ploeg AT. Long-term intravenous treatment of Pompe disease with recombinant human alpha-glucosidase from milk. Pediatrics 2004; 113:e448-57. [PMID: 15121988 DOI: 10.1542/peds.113.5.e448] [Citation(s) in RCA: 254] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Recent reports warn that the worldwide cell culture capacity is insufficient to fulfill the increasing demand for human protein drugs. Production in milk of transgenic animals is an attractive alternative. Kilogram quantities of product per year can be obtained at relatively low costs, even in small animals such as rabbits. We tested the long-term safety and efficacy of recombinant human -glucosidase (rhAGLU) from rabbit milk for the treatment of the lysosomal storage disorder Pompe disease. The disease occurs with an estimated frequency of 1 in 40,000 and is designated as orphan disease. The classic infantile form leads to death at a median age of 6 to 8 months and is diagnosed by absence of alpha-glucosidase activity and presence of fully deleterious mutations in the alpha-glucosidase gene. Cardiac hypertrophy is characteristically present. Loss of muscle strength prevents infants from achieving developmental milestones such as sitting, standing, and walking. Milder forms of the disease are associated with less severe mutations and partial deficiency of alpha-glucosidase. METHODS In the beginning of 1999, 4 critically ill patients with infantile Pompe disease (2.5-8 months of age) were enrolled in a single-center open-label study and treated intravenously with rhAGLU in a dose of 15 to 40 mg/kg/week. RESULTS Genotypes of patients were consistent with the most severe form of Pompe disease. Additional molecular analysis failed to detect processed forms of alpha-glucosidase (95, 76, and 70 kDa) in 3 of the 4 patients and revealed only a trace amount of the 95-kDa biosynthetic intermediate form in the fourth (patient 1). With the more sensitive detection method, 35S-methionine incorporation, we could detect low-level synthesis of -glucosidase in 3 of the 4 patients (patients 1, 2, and 4) with some posttranslation modification from 110 kDa to 95 kDa in 1 of them (patient 1). One patient (patient 3) remained totally deficient with both detection methods (negative for cross-reactive immunologic material [CRIM negative]). The alpha-glucosidase activity in skeletal muscle and fibroblasts of all 4 patients was below the lower limit of detection (<2% of normal). The rhAGLU was tolerated well by the patients during >3 years of treatment. Anti-rhAGLU immunoglobulin G titers initially increased during the first 20 to 48 weeks of therapy but declined thereafter. There was no consistent difference in antibody formation comparing CRIM-negative with CRIM-positive patients. Muscle alpha-glucosidase activity increased from <2% to 10% to 20% of normal in all patients during the first 12 weeks of treatment with 15 to 20 mg/kg/week. For optimizing the effect, the dose was increased to 40 mg/kg/week. This resulted, 12 weeks later, in normal alpha-glucosidase activity levels, which were maintained until the last measurement in week 72. Importantly, all 4 patients, including the patient without any endogenous alpha-glucosidase (CRIM negative), revealed mature 76- and 70-kDa forms of -glucosidase on Western blot. Conversion of the 110-kDa precursor from milk to mature 76/70-kDa alpha-glucosidase provides evidence that the enzyme is targeted to lysosomes, where this proteolytic processing occurs. At baseline, patients had severe glycogen storage in the quadriceps muscle as revealed by strong periodic acid-Schiff--positive staining and lacework patterns in hematoxylin and eosin--stained tissue sections. The muscle pathology correlated at each time point with severity of signs. Periodic acid-Schiff intensity diminished and number of vacuoles increased during the first 12 weeks of treatment. Twelve weeks after dose elevation, we observed signs of muscle regeneration in 3 of the 4 patients. Obvious improvement of muscular architecture was seen only in the patient who learned to walk. Clinical effects were significant. All patients survived beyond the age of 4 years, whereas untreated patients succumb at a median age of 6 to 8 months. The characteristic cardiac hypertrophy present at start of treatment diminished significantly. The left ventricular mass index decreased from 171 to 599 g/m2 (upper limit of normal 86.6 g/m2 for infants from 0 to 1 year) to 70 to 160 g/m2 during 84 weeks of treatment. In addition, we found a significant change of slope for the diastolic thickness of the left ventricular posterior wall against time at t = 0 for each separate patient. Remarkably, the younger patients (patients 1 and 3) showed no significant respiratory problems during the first 2 years of life. One of the younger patients recovered from a life-threatening bronchiolitis at the age of 1 year without sequelae, despite borderline oxygen saturations at inclusion. At the age of 2, however, she became ventilator dependent after surgical removal of an infected Port-A-Cath. She died at the age of 4 years and 3 months suddenly after a short period of intractable fever of >42 degrees C, unstable blood pressure, and coma. The respiratory course of patient 1 remained uneventful. The 2 older patients, who both were hypercapnic (partial pressure of carbon dioxide: 10.6 and 9.8 kPa; normal range: 4.5-6.8 kPa) at start of treatment, became ventilator dependent before the first infusion (patient 2) and after 10 weeks of therapy (patient 4). Patient 4 was gradually weaned from the ventilator after 1 year of high-dose treatment and was eventually completely ventilator-free for 5 days, but this situation could not be maintained. Currently, both patients are completely ventilator dependent. The most remarkable progress in motor function was seen in the younger patients (patients 1 and 3). They achieved motor milestones that are unmet in infantile Pompe disease. Patient 1 learned to crawl (12 months), walk (16 months), squat (18 months), and climb stairs (22 months), and patient 3 learned to sit unsupported. The Alberta Infant Motor Scale score for patients 2, 3, and 4 remained far below p5. Patient 1 followed the p5 of normal. CONCLUSION Our study shows that a safe and effective medicine can be produced in the milk of mammals and encourages additional development of enzyme replacement therapy for the several forms of Pompe disease. Restoration of skeletal muscle function and prevention of pulmonary insufficiency require dosing in the range of 20 to 40 mg/kg/week. The effect depends on residual muscle function at the start of treatment. Early start of treatment is required.
Collapse
Affiliation(s)
- Johanna M P Van den Hout
- Department of Pediatrics, Division of Metabolic Diseases and Genetics, Erasmus MC-Sophia, Rotterdam, Rotterdam, The Netherlands
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|